Eight COVID-19 vaccines have been approved somewhere in the world, at least for emergency use. In the U.S., only Moderna and Pfizer's two-dose mRNA vaccines are now available for distribution. But as the COVID pandemic continues to run rampant, vaccine supply everywhere remains limited. How did different countries decide who gets it and who doesn't? And what happens to the dozens of phase III clinical trials and their placebo participants who possibly qualify for vaccination with a different shot? To explore these and more ethical questions related to the COVID-19 vaccines, in this episode we speak with Arthur Caplan, PhD, director of the Division of Medical Ethics at NYU Grossman School of Medicine in New York City.